The variation of peak-to-average power ratio (PAPR) for different allocations of spreading code sequences in multi-carrier code division multiple access (MC-CDMA) and multi-carrier direct-sequence code division multiple access (MC-DS-CDMA) systems is investigated. The results show that for a small number of active users, the PAPR performance of an MC-CDMA system can be improved by careful allocation of the spreading code sequences to different users